-39.9% is the change from 990 to 595
Calculation steps:
[( 595 - 990 ) ÷ 990] x 100 = -39.9%
Formula
Percentage change = [(595 - 990) / 990] x 100
Subtract the new number by the original number
595 - 990 = -395
-395 ÷ 990 = -0.398989898989899
-0.398989898989899 x 100 = -39.9%